(19)
(11) EP 0 447 722 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
16.09.1992 Bulletin 1992/38

(43) Date of publication A2:
25.09.1991 Bulletin 1991/39

(21) Application number: 90313955.8

(22) Date of filing: 19.12.1990
(51) International Patent Classification (IPC)5C08F 4/646, C08F 10/00
(84) Designated Contracting States:
BE DE FR GB IT NL SE

(30) Priority: 26.12.1989 US 456916

(71) Applicant: MOBIL OIL CORPORATION
Fairfax, Virginia 22037-0001 (US)

(72) Inventor:
  • Kissin, Yuri Viktorovich
    East Brunswick, New Jersey 08816 (US)

(74) Representative: Colmer, Stephen Gary et al
European Office of Patent Counsel Mobil House 500-600 Witan Gate
Central Milton Keynes Buckinghamshire MK9 1ES
Central Milton Keynes Buckinghamshire MK9 1ES (GB)


(56) References cited: : 
   
     
    Remarks:
    The title of the invention has been amended (Guidelines for Examination in the EPO, A-III, 7.3).
     


    (54) Zirconium-based catalyst composition for polymerizing olefins


    (57) An olefin polymerization catalyst composition comprising:

    (1) a zirconium compound containing pi-bonded organic ligands and having the formula:



            CpmZrAnXq



    wherein:
    Cp represents an unsubstituted or substituted cyclopentadienyl group,
    m represents 1 or 2 or 3;
    A represents a halogen or hydrogen atom or a C₁ -C₆ alkyl group, a metalloalkyl group or a group of the formula:

    wherein:
    R represents a C₁ to C₁₀ alkyl group, a hydrogen, or halogen atom or a metalloalkyl group;
    X represents a halogen or hydrogen atom or C₁ to C₆ alkyl group; n represents 0, 1 or 2; and q represents 0, 1 or 2;
    providing that q+m+n is equal to the valence of zirconium; and

    (2) a catalyst activator which comprises a mixture of

    (i) an organoaluminum compound having the formula:



            Rp 'Al X' (k-p) or R3 'Al₂ X3'



    wherein:
    R' represents a C₁ to C₆ alkyl group;
    p represents 1 or 2;
    X' represents a halogen atom; and
    k represents the valence of aluminum; and

    (ii) a dialkylmagnesium compound having the formula:



            Mg Rt '' or Mg Rr ''R''' (t-r)



    wherein:
    R'' represents a C₂ to C₈ alkyl group;
    R''' differs from R'' and represents a C₂ to C₈ alkyl group;
    t represents the valence of magnesium; and
    r represents 0.01 to 1.







    Search report